1313722261 has 4 divisors (see below), whose sum is σ = 1335988800. Its totient is φ = 1291455724.

The previous prime is 1313722253. The next prime is 1313722279. The reversal of 1313722261 is 1622273131.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1313722261 - 2³ = 1313722253 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1313722231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11133181 + ... + 11133298.

It is an arithmetic number, because the mean of its divisors is an integer number (333997200).

Almost surely, 2^1313722261 is an apocalyptic number.

It is an amenable number.

1313722261 is a deficient number, since it is larger than the sum of its proper divisors (22266539).

1313722261 is an equidigital number, since it uses as much as digits as its factorization.

1313722261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22266538.

The product of its digits is 3024, while the sum is 28.

The square root of 1313722261 is about 36245.3067444600. The cubic root of 1313722261 is about 1095.2195471735.

Adding to 1313722261 its reverse (1622273131), we get a palindrome (2935995392).

The spelling of 1313722261 in words is "one billion, three hundred thirteen million, seven hundred twenty-two thousand, two hundred sixty-one".